1. Technical Field
The present invention relates to a droplet ejecting head, a droplet ejecting apparatus, a piezoelectric device, and a ceramic.
2. Related Art
A droplet ejecting apparatus, typified by an ink jet printer, is provided with a droplet ejecting head that ejects liquid. A typical example of the droplet ejecting head includes an ink jet recording head in which a piezoelectric actuator is operated to deform a pressure chamber with the result that ink contained in the pressure chamber is pressurized to be ejected as ink droplets from a nozzle hole. JP-A-2001-223404 discloses the piezoelectric actuator used in the ink jet recording head, and the disclosed piezoelectric actuator includes a piezoelectric ceramic that exhibits an electromechanical conversion function and that is disposed between electrodes. Piezoelectric devices, typified not only by the piezoelectric actuator but also by a piezoelectric sensor and various ultrasonic devices, are used in various apparatuses.
However, in view of environmental problems, lead-free (or low lead content) ceramic materials that are capable of exhibiting sufficiently good piezoelectric properties are currently being developed in order to replace lead zirconate titanate, which is typically used as a piezoelectric material. For example, in JP-A-2008-069051, a ceramic containing bismuth ferrate and bismuth potassium titanate is proposed as a lead-free piezoelectric ceramic.
Unfortunately, in cases where the ceramic containing bismuth ferrate and bismuth potassium titanate is used in a piezoelectric device, a problem of a high leakage current occurs.